There is a need to automatically sort documents which are fed through scanner systems to eliminate post document scanning manual handling and to eliminate sorting errors which can occur due to manual sorting operations. One example of a required sorting application is the sorting of payment checks from their accompanied forms and letters, which need to be scanned. In general, there is a need to sort documents based on their width, thickness, shape, condition, color, weight, document count and content.
Automatically sorting documents often requires devices such as a diverter gate actuated by a solenoid or other drive arrangements as shown in U.S. Pat. No. 7,777,919. In operation, diverter gates are often noisy when they are actuated, which is a significant issue in an office environment. Diverter gate devices require additional space along the document transport path which in turn increases the overall document feeding and sorting system size. Also, diverter gate devices add complexity to a document feeding and sorting system, and often require very high speed actuation which can require additional maintenance. Diverter gates can become a document jam point in a sorting system, because documents being sorted are often bent in the process of being transferred to different sorting bin or exit tray locations.
Other devices for sorting documents, such as using a suction cup device to pick and place documents, or using compressed air devices to blow documents to different sorting bin locations required vacuum or compressed air services, and require added space, complexity and operating expense.
Commonly assigned U.S. Pat. No. 7,828,279 discloses a method of scanning documents taken from an input tray and delivering them to an exit tray. The velocity of exit nip transport can be selected based on the timing of trailing edge detection. As taught in U.S. Pat. No. 7,828,279, controlling the exit nip velocity provides a way to maintain document stacking order for varying sizes and weights of documents.